Four decapitated bodies were found hanging from a bridge in the capital of western Mexico's Sinaloa state on Monday, part of a surge of cartel violence that killed 20 people in less than a day, authorities said.

Mexican authorities are investigating the deaths of twenty men in Sinaloa. The bodies were discovered near Culiacan with gunshot wounds. Some victims were decapitated. A message from a Sinaloa cartel faction was found.